Portable tree stand



FIG. 1 is a perspective view of a portable tree stand showing my new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a front elevational view thereof; and,

FIG. 7 is a rear elevational view thereof.

The broken lines in the figures represent stitching being part of the claimed design. 

The ornamental design for a portable tree stand, as shown and described. 